Stroke and power changing device.



No. 820,933. PATEN'TED MAY 15, 1906. H. A. LEWIS.

STROKE AND POWER CHANGING DEVICE.

APPLIOATION mm) mm: 18, 1904.

2 SHEETS*BHEET 1.

No. 820,933. .PATENTED MAY 15, 1906. H. A. LEWIS.

STROKE AND POWER CHANGING DEVICE.

Armxm nou FILED mm: 18, 1904.

2 SHEETS-SHEET 2.

UNITED STATES ,P ATENT OFFICE.

HARRY A. LEWIS, OF NORRISTOVVN, PENNSYLVANIA.

STROKE AND POWER CHANGING DEVICE.

Specification of Letters Patent.

Patented May 15, 1906.

Application filed June 18, 1904- Serial No. 213,111.

To all whom, it may concern:

Be it known that I, HARRY A. LEWIS, a citizen of the United States,residing at Norristown, in the county of Montgomery and State ofPennsylvania, have invented a certain new and useful Stroke and PowerChanging Device, of which the following is a specification.

The object of the present invention is to provide compact, reliable, andefficient power-transmission mechanism for converting speed into torqueor torque into speed, as may be required; and to this and other endshereinafter set forth the invention comprises the mechanism to bepresently described and finally claimed. 7

The nature, characteristic features, and scope of the invention will bemore fully understood from the following description,

taken in connection With the accompanying drawings, forming part hereof,and in which Figure 1 is a view principally in central sectionillustrating mechanism embodyin features of the invention. Fig. 2 is anend view, principally in elevation, looking toward the right in Fig. 1;and Fig. 3 is an end view of portions of the mechanism looking towardthe left in Fig. 1.

In the drawings, 2 may be considered to be the driving part, and 1 thedriven part, although this is interchangeable; but this assumption willbe made for the sake of clear ness throughout the following description.

3 represents portions of some fixed support, or are parts fixed inrespect to the mechanism itself.

4 is a shaft which normally revolves and is additionally turned when itis desired to change the ratio of speed and torque, as will behereinafter described. 7

5 is a tubular shaft arranged concentrically with and so as to rotateupon the shaft 4 and also in a bearing, as 6. Fast upon the left-handend of the shaft 5 is an arm 7, which of course turns around with it,and the eccentric carries upon its face a circular disk 8. This disknormally turns with the arm 7 as one piece; but when it is desired tochange the relation of speed and torque it may be turned in respect tothe arm 7, as will be described.

9 is a stud arranged to connect the parts 7 and 8 in such a way that thepart 8 may be turned in respect to the part 7. The shaft 1 has fast uponits left-hand end a toothed wheel 17, which meshes with internal teethin the part 8. The part 1 is pivoted by means of the stud 10 to the disk8 and power maybe taken from it by means of the ratchetarm a, pivoted toit at a, and the pawl b and ratchet-wheel b.

For the sake of explanation a description Will be given of how power istransmitted through the described mechanism, and for this purpose itwill be assumed that the shafts 1 and 5 are in some way connectedtogether. Thereafter. it will be explained how a change of the relativepositions of the shafts 4 and 5 effects a variationin the transmission.Assuming that the shafts 4: and 5 are in some Way caused to rotatetogether and that power is applied to the part 2, the arm 7 is turningaround the axis of the wheel 17 and is carrying the disk 8 andthere isno relative movement between the arm 7 and the part 8 and the wheel 17.Under the condit ons mentioned and illustrated in the drawings the stud10 is at the greatest possible distance from the axis of rotation of thearm 7, or, in other words, the axis of rotatlon of the arm 7 and stud 10are one hundred and eighty degrees apart. Thus there is transmitted themaximum of speed and the 1mmmum of torque. If now the shaft 4 be turnedand subsequently caused to rotate wlth the shaft 5, the effect will beto turn the disk 8 around its pivot 9, and thus brmg the stud 10 nearerto the axis of rotation of the arm 7-that is, the center of the shaft 1.If 1t Were turned through one hundred and eighty degrees, they would bein line with each other and the driven part 1 would not move. If it wereturned to intermediate pomts, there would clearly be a correspondingchange of speed and torque in the transmission.

A description will now be given of mechanism appropriate for turmng theparts 4 and 5 in respect to each other while the mechanism is running.Attached to the shaft 4 is an arm 18, which carries loose beveled gearsmeshing, respectively, with a beveled gear 19, secured. to the shaft 5and w th a beveled gear 20. The latter 1s fitted with an arm 21,positioned adjustably by means of worm-gearing 22, which can bepperated,as by hand-Wheel 23. The effect of th1s'gearingis well understood, andso long as the beveled gear 20 remains at rest the shafts 4 and 5 turntogether; but when the beveled gear 20 is turned one Way or the otherthose shafts 4 and 5 while still rotating are turned in respect to eachother, which is the object sought.

It will be obvious to those skilled in the art to which my inventionrelates that modifications may be made in details without departing fromthe spirit thereof. Hence the invention is not limited further than maybe required by the prior state of the art; but,

Having thus described the nature and ob j ects of the invention, what Iclaim as new, and desire to secure by Letters Patent, is

1. Power-transmission mechanism com prising a tubular shaft providedwith an arm, a disk centrally pivoted to the end of said arm andprovided with a stud or crank-pin and with internal teeth, and a secondshaft arranged in said tubular shaft and a pinion mounted thereonmeshing with said teeth, substantially as described.

2. Power-transmission mechanism comprising a driving part, a drivenpart, an arm connected With one of said parts, a disk centrally pivotedto the arm and provided with internal teeth and having pivotalconnection with the driven part, a pinion engaging said teeth,pawl-and-ratchet connections for the driven part, and means forchanging" the an gular relation between the aXis of rotation of the armand said pivotal connection, substantially as described.

3. Power-transmission mechanism comprising a driving part, a drivenpart, an arm carried by one of said parts, a toothed member havingpivotal connection with the other of said parts and rotatably mounted onthe arm, a toothed wheel meshing with the teeth of said member, atubular shaft carrying the arm, a shaft arranged Within the tubularshaft and carrying said toothed wheel, an arm connected with said shaft,sets of beveled gears carried by said arm, a beveled gear on saidtubular shaft meshing with one of the sets of beveled gears, a secondbeveled gear meshing with the other of said sets of beveled gears, andmeans for positioning and holding the last-mentioned beveled gear,substantially as described.

In testimony whereof I have hereunto signed my name.

HARRY A. LEWIS. In presence of O. F. LENHARDT, FRANK E. FRENCH.

